Thrust reversing variable area nozzle

ABSTRACT

A gas turbine engine system includes a first nozzle section associated with a gas turbine engine bypass passage and a second nozzle section that includes a plurality of positions relative to the first nozzle section. In at least one of the positions, there is a gap between the first nozzle section and the second nozzle section. A movable door between the first nozzle section and the second nozzle section selectively opens or closes the gap.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/872,143 filed on Oct. 15, 2007 now U.S. Pat. No. 8,006,479.

BACKGROUND OF THE INVENTION

This disclosure relates to gas turbine engines and, more particularly,to a gas turbine engine having a variable fan nozzle integrated with athrust reverser of the gas turbine engine.

Gas turbine engines are widely known and used for power generation andvehicle (e.g., aircraft) propulsion. One type of conventional gasturbine engine includes a compression section, a combustion section, anda turbine section that utilize a primary airflow into the engine togenerate power or propel the vehicle. The gas turbine engine may bemounted within a housing, such as a nacelle, depending on the vehicledesign. A bypass airflow flows through a passage between the housing andthe engine and exits from the engine at an outlet.

Presently, conventional thrust reversers are used to generate a reversethrust force to slow forward movement of a vehicle, such as an aircraft.Although effective, conventional thrust reversers serve only for thrustreversal and, when in a stowed position for non-landing conditions, donot provide additional functionality. Accordingly, there is a need for athrust reverser having additional functionality.

SUMMARY OF THE INVENTION

An example gas turbine engine system includes a first nozzle sectionassociated with a gas turbine engine bypass passage and a second nozzlesection having a plurality of positions relative to the first nozzlesection. In at least one of the positions, there is a gap between thefirst nozzle section and the second nozzle section. A movable door islocated at least partially between the first nozzle section and thesecond nozzle section for selectively opening or closing the gap.

In one example, the gas turbine engine system also includes a fan, acombustion section downstream of the fan, a turbine section downstreamof the combustion section, and the fan bypass passage is downstream fromthe fan.

An example method of controlling the gas turbine engine system includesselectively moving the second nozzle section relative to the firstnozzle section to establish a desired axial bypass flow through thenozzle and establish a gap between the first nozzle section and thesecond nozzle section. A door located at least partially between thefirst nozzle section and the second nozzle section may be selectivelymoved to open or close the gap.

BRIEF DESCRIPTION OF THE DRAWINGS

The various features and advantages of this invention will becomeapparent to those skilled in the art from the following detaileddescription of the currently preferred embodiment. The drawings thataccompany the detailed description can be briefly described as follows.

FIG. 1 illustrated selected portions of an example gas turbine enginesystem having a nozzle that integrated the variable area of control anda thrust reverser.

FIG. 2 illustrates selected portions of the nozzle in a first position.

FIG. 3 illustrates selected portions of the nozzle in a second position.

FIG. 4 illustrates selected portions of the nozzle in a third position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a schematic view of selected portions of an examplegas turbine engine 10 suspended from an engine pylon 12 of an aircraft,as is typical of an aircraft designed for subsonic operation. The gasturbine engine 10 is circumferentially disposed about an enginecenterline, or axial centerline axis A. The gas turbine engine 10includes a fan 14, a low pressure compressor 16 a, a high pressurecompressor 16 b, a combustion section 18, a low pressure turbine 20 a,and a high pressure turbine 20 b. As is well known in the art, aircompressed in the compressors 16 a, 16 b is mixed with fuel that isburned in the combustion section 18 and expanded in the turbines 20 aand 20 b. The turbines 20 a and 20 b are coupled for rotation with,respectively, rotors 22 and 24 (e.g., spools) to rotationally drive thecompressors 16 a, 16 b and the fan 14 in response to the expansion. Inthis example, the rotor 22 also drives the fan 14 through a gear train25.

In the example shown, the gas turbine engine 10 is a high bypassturbofan arrangement. In one example, the bypass ratio is greater than10, and the fan 14 diameter is substantially larger than the diameter ofthe low pressure compressor 16 a. The low pressure turbine 20 a has apressure ratio that is greater than 5, in one example. The gear train 25is an epicycle gear train, for example, a star gear train, providing agear reduction ratio of greater than 2.5. It should be understood,however, that the above parameters are only exemplary of a contemplatedgeared architecture engine. That is, the disclosed examples areapplicable to other engines.

An outer housing, nacelle 28, (also commonly referred to as a fannacelle) extends circumferentially about the fan 14. A fan bypasspassage 32 extends between the nacelle 28 and an inner housing, innercowl 34, which generally surrounds the compressors 16 a, 16 b andturbines 20 a, 20 b. In this example, the gas turbine engine 10 includesa nozzle 30 that is coupled with the nacelle 28. The nozzle 30integrates functions of a variable fan nozzle and a thrust reverser, aswill be described below.

In operation, the fan 14 draws air into the gas turbine engine 10 as acore flow, C, and into the bypass passage 32 as a bypass air flow, D.The bypass air flow D is discharged axially as a discharge flow througha rear exhaust 36 associated with the nozzle 30 near the rear of thenacelle 28 in this example. The core flow C is discharged from a passagebetween the inner cowl 34 and a tail cone 38.

For the gas turbine engine 10 shown FIG. 1, a significant amount ofthrust may be provided by the discharge flow D due to the high bypassratio. Thrust is a function of density, velocity, and area. One or moreof these parameters can be manipulated to vary the amount and directionof thrust provided or to enhance conditions for aircraft control,operation of the fan 14, operation of other components associated withthe bypass passage 32, or operation of the gas turbine engine 10. Forexample, an effective change in a cross-sectional area of the rearexhaust 36 causes an air pressure change within the bypass passage 32that in turn changes a pressure ratio across the fan 14. Thus, differentcross-sectional areas may be desired for different flight conditions,such as aircraft cruise and take-off.

In the disclosed example, the nozzle 30 may be used to control thecross-sectional area of the rear exhaust 36. However, it should beunderstood that the bypass flow or discharge flow D may be effectivelyaltered through other features, for example, by altering a flow boundarylayer. Furthermore, it should be understood that effectively alteringthe cross-sectional area of the rear exhaust 36 is not limited tophysical locations approximate to the exit of the nacelle 28, butrather, includes altering the bypass flow D by any suitable means at anysuitable location along the length of the engine 10.

Referring to FIG. 2, the nozzle 30 in this example includes a firstnozzle section 40 a and a second nozzle section 40 b that is axially aftof the first nozzle section 40 a. The first nozzle section 40 a is anaft end of the nacelle 28; however, the first nozzle section 40 a mayalternatively be a separate piece that is coupled to the nacelle 28. Thefirst nozzle section 40 a and the second nozzle section 40 b includerespective outer surfaces 42 a and 42 b and respective inner surfaces 44a and 44 b relative to the engine centerline A.

In this example, the second nozzle section 40 b is axially translatablerelative to the first nozzle section 40 a using an actuator 46. Theactuator is connected with the second nozzle section 40 b through alinkage 48, which may include any suitable type of linkage such as, butnot limited to, a telescopic linkage.

It is to be understood that the nozzle 30 may include a plurality of thesecond nozzle sections 40 b arranged circumferentially around the bypasspassage 32. In this regard, the first nozzle section 40 a and the secondnozzle section 40 b at least partially form an outer surface of thebypass passage 32, while the nacelle 28 forms the axially forwardportion of the bypass passage 32 and the inner cowl 34 forms an innersurface of the bypass passage 32. Depending upon the number of secondnozzle sections 40 b that are used, a corresponding number of theactuators 46 may be used to selectively move the second nozzle sections40 b. The actuators 46 are in communication with a controller 50 toselectively axially translate the second nozzle sections 40 b. Thecontroller 50 may be dedicated to controlling the nozzle 30, integratedinto an existing engine controller within the gas turbine engine 10, orbe incorporated with other known aircraft or engine controls.Additionally, the controller 50 and the actuators 46 may be mounted inother locations than shown in this example.

A movable door 52 is at least partially between the first nozzle section40 a and the second nozzle section 40 b. The movable door 52 includes aninner surface 54 a and an outer surface 54 b that is spaced apart fromthe inner surface 54 a to form a pocket 56 therebetween. A side 57connects the inner surface 54 a and the outer surface 54 b. In thedisclosed example, the outer surface 54 b of the moveable door 52 isapproximately flush with the outer surface 42 a of the first nozzlesection 40 a and the outer surface 42 b of the second nozzle section 40b to maintain an aerodynamic profile of the engine 10, as will bediscussed below.

The moveable door 52 is also connected with the actuator 46 through thelinkage 48, which may include multiple telescopic links. In this regard,the actuator 46 is a dual mode actuator that can move the second nozzlesection 40 b and the movable door 52 independently of each other.Alternatively, a separate actuator may be used to independently move themovable door 52.

A thrust reverse cascade 58 is received at least partially within thepocket 56. The thrust reverse cascade 58 includes vents 60 (shownschematically) for achieving a thrust reversing effect, such as bychanging a direction of the discharge flow D. The thrust reverse cascademay also include guides, such as tracks 59, shown schematically, forguiding and supporting the moveable door 52 and linkage 48.

In operation, the controller 50 selectively commands the actuator 46 tomove the second nozzle section 40 b between a first position (FIG. 2)and a second position (FIG. 3) to thereby control a nozzlecross-sectional flow area 62. The second nozzle section 40 b may also bemoved to intermediate positions between the positions shown. It is to beunderstood that the controller 50 may command multiple actuators 46 tomove multiple second nozzle sections 40 b in concert, or independentlyif desired. In the first position as shown in FIG. 2, the second nozzlesection 40 b is axially forward and is received against the first nozzlesection 40 a. A seal 61 may be provided between the first nozzle section40 a and the second nozzle section 40 b to prevent the discharge flow Dfrom leaking therebetween.

The controller 50 selectively commands the actuator 46 to translate thesecond nozzle section 40 b axially rearward relative to the first nozzlesection 40 a to the second position as illustrated in FIG. 3. In thesecond position, there is a gap 64 (represented by a dashed arrow)between the first nozzle section 40 a and the second nozzle section 40b. As will be described more fully below, the moveable door 52 isoperative to selectively open or close the gap 64.

Movement of the second nozzle section 40 b axially rearward increasesthe nozzle cross-sectional flow area 62 to nozzle cross-sectional flowarea 66. In the illustrated examples, the nozzle cross-sectional flowarea corresponds to a distance between the aft end of the second nozzlesection 40 b and the inner cowl 34. However, given this description, oneof ordinary skill in the art will recognize that the nozzle area may bedefined at other locations or using other components.

The increased nozzle cross-sectional flow area 66 provides additionalaxial area for exit of the discharge flow D from the bypass passage 32to thereby alter a pressure in the bypass passage 32. For example, thesecond nozzle section 40 b may be moved between the positions shown inFIGS. 2 and 3 based on flight conditions, such as in response to cruiseor take-off, for example. Thus, the nozzle 30 functions to providevariable area capability.

The moveable door 52 also maintains an aerodynamic profile of the engine10 during operation of the second nozzle section 40 b to control thenozzle cross-sectional area. For example, the outer surface 54 b of themoveable door 52 is approximately flush with the outer surfaces 42 a and42 b. That is, the outer surface 54 b is slightly radially inwards ofthe outer surfaces 42 a and 42 b to permit the moveable door 52 to fitwithin the interiors of the nozzle sections 40 a and 40 b but is notoffset so much as to cause a large aerodynamic disturbance of airflowover the nacelle 28 and nozzle 30. In some examples, the outer surface54 b may contact the inner sides of the walls forming the outer surfaces42 a and 42 b. In other examples, the outer surface 54 a may be spaced afew millimeters or even a few centimeters from the walls forming theouter surfaces 42 a and 42 b, depending on how much of an aerodynamicdisturbance is tolerable.

In the illustrated example, the nozzle 30 also functions as a thrustreverser. A thrust reverse blocker door 68 is connected for movementwith the moveable door 52 through a linkage 70. For example, the linkage70 may be connected with the movable door 52 using a pin connection orother suitable type of connection. In this example, the thrust reverseblocker door 68 includes a free end 72 and a fixed end 74 that isconnected with a pivot 76.

The controller 50 selectively commands the actuator 46 to move themovable door 52, which in turn moves the thrust reverse blocker door 68.It is to be understood that the controller 50 may command multipleactuators 46 to move multiple moveable doors 52 and thrust reverseblocker doors 68. The controller 50 and actuator 46 move the movabledoor 52 from the closed position illustrated in FIG. 3 to the openposition illustrated in FIG. 4 to achieve a thrust reversing effect, forexample.

As can be appreciated from FIGS. 3 and 4, movement of the movable door52 selectively opens or closes the gap 64 between the first nozzlesection 40 a and the second nozzle section 40 b. Thus, in the closedposition (FIG. 3), the movable door 52 prevents flow through the gap 64from the bypass passage 32 and the thrust reverse blocker door 68 is ina stowed position substantially out of the bypass passage 32.

When thrust reversing is desired, such as after landing, the controller50 and actuator 46 translate the moveable door 52 axially forward to theopen position (FIG. 4). Movement of the moveable door 52 pulls thelinkage 72 and causes the thrust reverse blocker door 68 to rotate aboutthe pivot 76 to a deployed position such that the free end 72 movesradially outwards from the inner cowl 34 toward the second nozzlesection 40 b. In the illustrated example, the free end 72 may abutagainst the inner surface 44 b of the second nozzle section 40 b anddefect the discharge flow D outwards through the gap 64 and vents 60 ofthe thrust reverse cascade 58 for a thrust reversing effect.

As can be appreciated from the disclosed examples, the example nozzle 30integrates the functions of controlling the nozzle cross-sectional flowarea and thrust reversing. That is, the controller 50 and actuator 46move the second nozzle section 40 b and the moveable door 52 to controlthe nozzle cross-sectional flow area and thrust reversing. Moreover,because movement of the moveable door 52 is independent of movement ofthe second nozzle section 40 b, the controller 50 and actuator 46 cancontrol the nozzle cross-sectional area without thrust reversing.Additionally, the disclosed nozzle 30 is compact because the secondnozzle section 40 b does not require additional aft movement to achievethe thrust reversing, which is controlled through separate forwardmovement of the movable door 52.

Although a combination of features is shown in the illustrated examples,not all of them need to be combined to realize the benefits of variousembodiments of this disclosure. In other words, a system designedaccording to an embodiment of this disclosure will not necessarilyinclude all of the features shown in any one of the Figures or all ofthe portions schematically shown in the Figures. Moreover, selectedfeatures of one example embodiment may be combined with selectedfeatures of other example embodiments.

The preceding description is exemplary rather than limiting in nature.Variations and modifications to the disclosed examples may becomeapparent to those skilled in the art that do not necessarily depart fromthe essence of this disclosure. The scope of legal protection given tothis disclosure can only be determined by studying the following claims.

What is claimed is:
 1. A gas turbine engine system, comprising: a firstnozzle section; a second nozzle section, wherein the first nozzlesection and the second nozzle section at least partially define a gasturbine engine bypass passage, wherein the second nozzle section isaxially translatable relative to the first nozzle section such thatthere is a gap between the first nozzle section and the second nozzlesection when the second nozzle section is moved from a first position toa second position; and a moveable door at least partially between thefirst nozzle section and the second nozzle section for selectivelyopening and closing the gap, wherein the moveable door includes a thrustreverse cascade between a radially inner surface of the moveable doorand a radially outer surface of the moveable door relative to an enginecenterline, the thrust reverse cascade including tracks to guide themoveable door during axial translation.
 2. The gas turbine engine systemas recited in claim 1, wherein the gas turbine engine bypass passageincludes a radially inner surface and a radially outer surface relativeto an engine centerline, and the first nozzle section and the secondnozzle section form at least a portion of the radially outer surface. 3.The gas turbine engine system as recited in claim 2, wherein the movabledoor is located radially outwards of the gas turbine engine bypasspassage relative to the engine centerline axis.
 4. The gas turbineengine system as recited in claim 1, including a thrust reverse blockerdoor connected to the moveable door via a linkage.
 5. The gas turbineengine as recited in claim 4, wherein the thrust reverse blocker doorrotates axially forward in response to movement of the moveable door. 6.The gas turbine engine system as recited in claim 1, wherein thrustreverse cascade includes a plurality of vents.
 7. The gas turbine enginesystem as recited in claim 6, wherein the plurality of vents change thedirection of airflow in the gas turbine engine bypass passage.
 8. Thegas turbine engine system as recited in claim 1, further comprising aseal between the first nozzle section and the second nozzle section inthe first position.
 9. The gas turbine engine system as recited in claim1, wherein the moveable door includes an axially forward side attachedto the radially inner side of the moveable door and the radially outerside of the moveable door, wherein the axially forward side is connectedto an actuator via a linkage.
 10. The gas turbine engine system of claim1, wherein the combustion section and the turbine section define a coreairflow passage, wherein the gas turbine fan bypass passage is radiallyoutward of the core airflow passage.
 11. The gas turbine engine of claim10, wherein the core airflow is discharged from the core airflow passagebetween an inner cowl and a tail cone.
 12. The gas turbine engine systemof claim 1, wherein the gas turbine fan bypass passage is in fluidcommunication with the fan.
 13. The gas turbine engine system of claim1, wherein the gas turbine bypass passage bypasses a compressor section,a combustor section, and a turbine section.
 14. A gas turbine enginesystem, comprising: a fan; a combustion section downstream of the fan; aturbine section downstream of the combustion section; a fan bypasspassage downstream from the fan; a nozzle defining at least a portion ofthe fan bypass passage and having a first nozzle section and a secondnozzle section axially translatable relative to the first nozzle sectionsuch that there is a gap between the first nozzle section and the secondnozzle section when the second nozzle section is moved from a firstposition to a second position; and a moveable door at least partiallybetween the first nozzle section and the second nozzle section forselectively opening and closing the gap, wherein an actuator is attachedto the moveable door to move the moveable door independent of the secondnozzle section.
 15. The gas turbine engine system of claim 14, whereinthe actuator is connected to the moveable door and the second nozzlesection using a linkage with a plurality of telescopic links.
 16. Thegas turbine engine system of claim 15, wherein the moveable doorincludes a thrust reverse cascade between a radially inner surface ofthe moveable door and a radially outer surface of the moveable doorrelative to an engine centerline, the thrust reverse cascade includingtracks guiding the moveable door during axial translation.
 17. The gasturbine engine system as recited in claim 14, further including a thrustreverse blocker door pivotably attached to an inner cowl, wherein theinner cowl defines a radially inner side of the fan bypass passage. 18.The gas turbine engine system as recited in claim 17, wherein the thrustreverse blocker door is attached to the inner cowl on a first end and toa linkage on a second end, wherein the linkage is attached to themoveable door, wherein the thrust reverse blocker door moves in responseto movement of the moveable door.
 19. The gas turbine engine as recitedin claim 17, wherein the thrust reverse blocker door moves in the sameaxial direction as the moveable door when moving from an closed positionto an open position.
 20. The gas turbine engine system of claim 17,wherein the thrust reverse blocker door includes a free end and a fixedend.
 21. The gas turbine engine system of claim 14, wherein thecombustion section and the turbine section define a core airflowpassage, wherein the fan bypass passage is radially outward of the coreairflow passage.
 22. A gas turbine engine system, comprising: a firstnozzle section; a second nozzle section, wherein the first nozzlesection and the second nozzle section at least partially define a gasturbine engine bypass passage, wherein the second nozzle section isaxially translatable relative to the first nozzle section such thatthere is a gap between the first nozzle section and the second nozzlesection when the second nozzle section is moved from a first position toa second position; and a moveable door at least partially between thefirst nozzle section and the second nozzle section for selectivelyopening and closing the gap, wherein the moveable door is independentlymoveable relative to the second nozzle section, wherein the moveabledoor includes a thrust reverse cascade between a radially inner surfaceof the moveable door and a radially outer surface of the moveable doorrelative to an engine centerline, the thrust reverse cascade includingtracks guiding the moveable door during axial translation.
 23. The gasturbine engine system as recited in claim 22, wherein a first actuatoraxially translates the second nozzle section and a second actuatoraxially translates the moveable door.
 24. The gas turbine engine systemas recited in claim 23, wherein the first actuator axially translatesthe second nozzle section in an axial direction opposite the axialtranslation of the second nozzle section during thrust reversing. 25.The gas turbine engine system as recited in claim 24, further includinga thrust reverse blocker door for thrust reversing.
 26. A gas turbineengine system comprising: a fan disposed about an engine centerline; afan bypass passage downstream from the fan; a nozzle defining at least aportion of the fan bypass passage and having a first nozzle section anda second nozzle section axially translatable relative to the firstnozzle section such that there is a gap between the first nozzle sectionand the second nozzle section when the second nozzle section is movedfrom a first position to a second position; and a moveable door at leastpartially between the first nozzle section and the second nozzle sectionfor selectively opening and closing the gap, wherein an actuator isattached to the moveable door to move the moveable door independent ofthe second nozzle section; a gear train having a reduction ratio ofgreater than 2.5:1, wherein the gear train drives the fan; a lowpressure compressor disposed about the engine centerline, wherein thefan has a diameter greater than a diameter of the low pressurecompressor, the gas turbine engine system having a bypass ratio greaterthan 10:1; a high pressure compressor; a combustion section; a highpressure turbine that drives the high pressure compressor; and a lowpressure turbine having a pressure ratio greater than 5:1, wherein thelow pressure turbine drives the low pressure compressor and the geartrain.
 27. The gas turbine engine system of claim 26, wherein the fandraws air flow into the fan bypass passage, air flow exits the fanbypass passage at an exhaust having a variable cross-sectional area,wherein thrust generated by the gas turbine engine system variesrelative to the variable cross-sectional area of said exhaust.
 28. Thegas turbine engine system of claim 26, wherein the fan draws air flowinto the fan bypass passage, air flow exits the fan bypass passage at anexhaust having a variable cross-sectional area, wherein the pressureratio across the fan varies relative to the variable cross-sectionalarea of said exhaust.